Unsystematic = Unmemorable?

Etienne Gilson, From The Spirit of Thomism (1964):

Toward the end of the nineteenth century, a German philosopher by the name of Franz Brentano began to wonder how long the chain of the mutually destructive systems of philosophy was going to continue. Kant had just been replaced by Fichte, Fichte by Schelling, Schelling by Hegel, and Hegel by Schopenhauer. Hoping to bring the philosophical merry-go-round to a stop, Brentano suggested as a remedy a general return to the realism of the Greeks. This meant that for us as already for Aristotle, the method of philosophy should be the same as that of the science of nature, to wit, a rational interpretation of observed facts. The result of Brentano’s experiment is conclusive: himself a good psychologist, Brentano left no system to which his name could be attached, so that today he is practically forgotten.

I must confess that I know of no remedy to the difficulty. … Philosophy simply is not the kind of conceptual poetry they call a philosophical ‘system.’ Philosophy is wisdom, and wisdom is not poetry. Neither is it positive science, nor ethics, nor economics, nor politics. A true philosopher may well be neither a scientist nor a successful industrialist, nor a celebrated statesman. When asked to say what he knows, the true philosopher modestly answers with Socrates: nothing. And indeed his own function is not to know any particular kind of things; rather, it is to start from the cognitions gained by other men in the various and changing fields of knowledge and action; it is to clarify these cognitions, to criticize them and to order them by relating them to first causes. Like science, philosophy is about things, not cognitions, yet what is left of science, unless it thus unifies itself in the light of philosophical reflection, is but a heap of uncritical and disjointed pieces of information.